Pilz/Pilz.Networking/Api/ApiServer.cs

using System.Reflection;

namespace Pilz.Networking.Api;

public class ApiServer : ApiClient, IApiServer
{
    protected readonly Dictionary<string, object> handlers = [];
    protected readonly Dictionary<Type, IMessageSerializer> serializers = [];

    public IMessageSerializer Serializer { get; set; } = new DefaultMessageSerializer();

    public virtual void RegisterHandler<T>(string url, T instance) where T : class
    {
        var methods = typeof(T).GetMethods(BindingFlags.Instance | BindingFlags.Public);

        foreach (var method in methods)
        {
            if (method.GetCustomAttribute<MessageHandlerAttribute>() is not MessageHandlerAttribute attribute
                || method.GetParameters().FirstOrDefault() is not ParameterInfo parameterInfo
                || !parameterInfo.ParameterType.IsAssignableTo(typeof(ApiMessage)))
                continue;


            var serializer = Serializer;
            if (attribute.Serializer is not null)
            {
                if (serializers.TryGetValue(attribute.Serializer, out var s) && s is not null)
                    serializer = s;
                else if (Activator.CreateInstance(attribute.Serializer) is IMessageSerializer ss)
                {
                    serializer = ss;
                    serializers.Add(attribute.Serializer, ss);
                }
            }

            // ...
        }
    }

    public virtual void RegisterHandler(string url, Delegate handler)
    {
        // ...
    }

    protected virtual string? HandleMessage(string url, string json)
    {
        // ...
    }
}